The field of the invention relates generally to semiconductor devices, and more specifically, to reticles used to form semiconductor devices.
As semiconductor device dimensions shrink, semiconductor device feature density increases. Thus, physical dimensions of features and spaces between the features decrease. Since the spaces between the features are smaller, if the decreased features"" physical dimensions are not well controlled adjacent features may merge. If the features are conductive, they will short together. Alternatively, the features can be smaller than desired and thus not perform as required. For example, a feature can be too small to provide enough current to another feature. Thus, in order for the semiconductor device to function properly the physical dimensions of the features must be well controlled.
In order to measure the control of the physical dimensions, the width of a feature, typically the smallest feature, is monitored through the manufacturing process. This measurement is termed critical dimension (CD).
The CD of a feature can be altered during reticle manufacturing, which impacts the resulting CD on the semiconductor wafer and often decreases manufacturing yield, circuit performance or device reliability. In other words, the CD of a feature during reticle manufacturing can have an adverse effect on the cost and/or performance of the semiconductor device. Thus, a need exists to control the CD of features during the reticle manufacturing process.